Electric soldering iron



l.. F. YOUNG ELECTRIC SOLDERING IRON 2@ 2i @1795. ummlmlmulm 11-'.

Filed June 20, 19.34

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INVENTOR Zeonanfzzzzg. I

hip ATTORNEY Patented Mar. 9, 1937 UNITED STATES PATENT OFFICE 8 Claims.

The present invention relates to electric heating devices in general,and particularly to what is known as electric soldering iron, and thelike.

The principal objects of the present invention 5 are to provide a highlyefilcient, inexpensively fabricable device of this kind in which themost important part, the heating element is so constructed as to combinesimplicity of structure, eiciency in operation, and inexpensiveness in lmanufacture, as well as ready exchangeability when required.

A further object of this invention is to provide a heating member inwhich the heating element or resistance is hermetically sealed againstoxil dation within a hollow casing of highly heatconductive material,and in which the element is tightly packed by a high heat-conductive,pourable, crystalline or amorphous dielectric, adapted to maintain thewindings of the element in de- 20 sired position within the casing.

A still further object of this invention is to provide within theheating member a suitable element support, by means of which the elementmay be suspended within the casing in a plural- 25 ity of courses, so asto provide the maximum radiating surface possible, distributed in themost uniform relation in respect to the casing.

Still another object of this invention is to provide terminals for theelement, adapted to extend 30 from the sealed casing and equipped withfrictional means, designed to engage the element support in such a wayas to maintain the element in its desired expanded position until thepowderformed dielectric completely fills all available 35 space withinthe casing so that each portion oi the element is tightly packed,supported and reinforced by the dielectric; the terminals are alsoinstrumental in holding the element support in a floating positionWithin the casing, until packed 40 tightly in place by the dielectric.

A still further object of this invention is to provide in conjunctionwith the heating member an outer housing made of one piece of materialand having two portions of varying diame- 45 ters, the housing portionof the larger diameter adapted to receive said heating member andiurther adapted to provide air circulation between the heating memberand the housing, whereby the housing is kept relatively cool, thusprevent- 50 ing injury to the handle of the device.

A further object of this invention is to provide for the leads,extending from the heating member, a suitable insulator havingthroughpassages which terminate in channel formations,

55 said passages adapted to accommodate the greater part of the leads,while said channel formations are intended to receive the bent-overconnections between the lead ends and exterior electric conductorsentering the handle of the device.

A still further object of this invention is to provide in conjunctionwith the housing portion of the smaller diameter a dielectric handle,having the added property of not being heat conductive, said handleprovided with a' depression for receiving attaching means, adapted toengage the smaller housing portion, said depressions being of sufficientdepth to receive said attaching means in such a way as to precludecontact therewith, while the handle is being held.

The foregoing and a great many other objects and advantages of thisinvention will become more fully apparent from the ensuing description,in connection with the accompanying drawing, which latter, althoughforming a part of this invention, are not intended to limit the same tothe actual showing, and in which Fig. l is a longitudinalcross-sectional View through one form of the present invention,

Fig. 2 is an enlarged longitudinal cross-sectional view of the heatingmember portion of the device,

Fig. 3 is a perspective View, partially in section of an assembly,comprising the heating element, the element support and the terminal orlead insulator,

Fig. 4 is an enlarged end View of the element support, showing theelement suspended therein, as observed in the direction of lines ll--llof Figure 3,

Fig. 5 is a cross-sectional View through the terminal insulator, takenon lines A5--5 of Figure l, and showing the channel formations,

Fig. 6 is a longitudinal cross-sectional View of the element casing,

Fig. 7 is a longitudinal cross-sectional View through the outer housingof this device,

Fig. 8 illustrates the heating element in its original close, helicalform, with the terminals or leads attached,

Fig. 9 illustrates a diagrammatical View of the expanded element as itwould appear when borne by the support,

Fig. 10 illustrates a miniature melting pot, as one of the exchangeabletools heatable by the device, and

Figs. 11 and l2 are cross-sectional views through modined heatingmembers, terminating in miniature melting pots, and

Fig. 13 is an enlarged end View of a modified form of an elementsupport.

Referring now specifically to the figures,

numeral In denotes the outer housing of the device, made preferably ofone piece of tubing, and consisting of a portion I having a largerdiameter and a portion I2 of a smaller diameter. At the end of thelarger portion there are provided apertures I 3 for receiving elementcasing attaching means, while at the housing portion of the smallerdiameter there will be noted an aperture Ill adapted to receiveattaching means I 5 imbedded in depression IE of handle I'I. (See Fig.1.) The larger housing portion is secured by rivets or screws I8, passedthrough openings I3 into suitable holes provided in enlargement or headI 9 of the element casing 20. The latter consists of a hollow cylinder,open at one end and closed by the head formation IS, within which latteris provided a threaded socket 2i for receiving, and conductivelyconnecting therewith a heatable tool, as for instance a tip 22 or amelting pot 23, such as illustrated in Figure 10. Obviously any otherheatable tool may be inserted and heat-conductively connected with headI9, since the tools are intended to be exchangeable in thisconstruction.

Adjacent to the closed head portion of the casing there is provided aninsulator disc 24, such as mica, the purpose of which will be explainedpresently. Into the casing there is inserted an element support 25,consisting of a cylinder made of dielectric material and provided with aplurality of through-passages 25, which are preferably cylindrical inform. A heating element 27, originally comprising a close helix, asshown in Figure 8, is connected at its two ends 28 to leads or terminals29. The portion of the terminals, immediately adjacent to theirconnections with the element, are curved in a wave-like form, as seen at30, so as to frictionally engage the interior of two passages providedin the element support. In Figures 3 and 4 the element support is'shownto have four such through-passages, and the element is in engagementwith all four of them.

vIn this construction the insertion of the element is accomplished asfollows: Both terminals, to which the ends of the element are attached,are first passed through two of the passages and then returned throughthe two other passages. By these successive operations the originallyclose helix is stretched so that each winding of the helix is separatedfrom the other. The wavelike ends of the terminals frictionally engagethe walls of their respective passages and thus hold the element in itsstretched position within the support. While being held by theterminals, the support with the stretched element therein, is insertedinto the casing so that the portions 3l of the element, shown clearly inFigure 9, bear against insulating disc 2li rst inserted into the casing.Element support 25 is now held equally spaced from the interior wall ofthe casing, so as to assume a oating position therewithin. VNow allavailable space within the through-passages and between the individualwindings of the element, and between the element support and the casingis completely lled and tightly packed by a pourable, sand-like oramorphous dielectric indicated at 32. While the process of packing thedielectric into the casing is taking place, the frictional engagement ofthe wave-like formation of the terminals with the through-passages ofthe element support prevents a displacement of the element windingswithin the support.

It will be observed that the element casing is somewhat longer than theelement support, so that the latter is completely housed, and is capableof being hermetically sealed therewithin. The seal is clearly indicatedat 33. It consists of a heat resisting dielectric substance which willreadily adhere to the metallic surfaces of the casing and of theterminals, and which has the same coefficient of expansion as that ofthe metal.

Adjacent to seal 33, and extending therefrom through the reduced portionI2 of the housing, and beyond the housing into handle I1, there will beobserved a terminal or lead insulator 36, comprising a cylindricalstructure with two through-passages 35, which latter terminate intochannel formations 36. These channel formations are adapted to receivethe connections between the terminals and the exterior electricconductors 37 entering the outer end of handle I 'i'. The connectionbetween the terminals and these conductors is preferably accomplished inthe following manner: The ends of the terminals are passed throughpassages 35 and bent over and out at right angles to the channelformations. The ends of the electric conductors are bent in similar wayand then the terminals and the conductors are twisted together in theapproved fashion and either soldered or welded together; now theconnections are bent backwards, in the direction indicated by the arrowin Figure 3, and clearly seen in their final position in Figure l. Thechannels completely house these connections, insulate them, and preventundesired bulkiness usually found in similar devices. These connectionsalso decidedly reduce the cost of the device, in that screw attachmentsor similar wire connecting means are successfully eliminated thereby,thus greatly simplifying production. The arrangement of the elementcasing and of the insulator for the terminals within the outer housingprovides a very beneficial air space so that air circulation Within thehousing and the handle may be provided. In order to promote circulationsuitable air holes 38 may be arranged in the larger housing portionadjacent to the element housing. There is sufficient air space providedwithin the handle for cold air to enter therein, whereas hot air may bedispelled through L.

aperture 38.

Referring now to the modified forms of the element housing shown inFigures 11 and 12, the latter are primarily intended for use inconnection with heating devices where the heating tools i is to bepermanently attached to, or is to be integral with the heating member.In Figure 11 is shown a miniature melting pot 39 provided with a tubularextension 40, adapted to serve as element casing of the device, and isprovided with a stepped-up connecting enlargement 6I to which housing 2is secured in similar manner as shown in Figure l.

When it is desired that more intense heat be supplied to the potformation, the position of the element casing may be changed, asproposed in Figure 12. In this figure the element casing 43 extendsbelow the bottom of melting pot Gd. In all other respects theconstruction of the element casing and its attaching provisions to thehousing is the same as in Figures 1 and 1l.

In Figure 13 there is illustrated an element support 25', provided withtwo through-passages 45, and with two outwardly open channels 4t,corresponding to the two other through-passages of the support shown inFigure 4. This modified construction of the element support possessesthe advantage of facilitating a more ready .attachment of the elementthereto, permits a better distribution of its expanded windings, andpromotes more direct heat radiation from those parts of the elementwhich are held in the chan-- nels.

From the foregoing description of the few specific forms of the presentinvention it becomes evident that a good many variations may be providedin order to enhance the quality of, and to adapt the device for variousspecic purposes and uses.

Due to the compact and simple arrangement of the sealed heating member,the latter may be readily exchanged, in which case its attachingprovisions to the outer housing will require some slight alterations. Inany modied form, however, there is always provided sufficient air spacebetween the element casing and the housing, so as to promote aircirculation and cooling of the housing, tonot only preserve the handle,but also to maintain a perfect connection between the handle and thesmaller housing portion secured thereto.

While I am aware of the existence of heating devices, designed to servesimilar purposes to that oi the present invention, l do not know, to thebest of my knowledge, of any devices employing the principles ofconstruction described above, and having in mind the possible necessityof varying the details of the construction illustrated, I herewithreserve for myself the right to modify, and improve thereupon, withoutdeparting from the broad scope of my idea, as set forth in the annexedclaims.

I claim:

l. In an electric heating device, the combination with a tubular,one-piece outer housing, having two portions of different diameters, ofan element casing disposed partially within and secured to the housingportion of larger diameter, said casing comprising an integral, hollowcylindrical member, made of heat conductive material, and provided withan enlarged, closed end extending beyond, and in engagement with saidlarger housing portion, and including means for removably attaching aheatable tool thereto; the other, or inner end of said casing beingopen, a heating element within said casing, hermetica-lly sealing andterminal holding means provided at the open end of said casing; aninsulating element within, and next to the enlarged end of said casing,a pair of heating element terminals secured within, and extending fromsaid sealing and terminal holding means, an insulator for saidterminals, extending from said casing into the housing portion of thesmaller diameter, and provided with interior passag-es and end channels,the latter serving for accommodating the connections between theterminals and exterior electric conductors.

2. In an electric heating device, as set forth in claim l, a handle inengagement with the end of the housing portion of the lesser diameter,and means imbedded in said handle for retaining the latter and saidhousing portion at desired relation to one another.

3. In a heating device, the combination with a tubular, one piecehousing having one portion of a smaller, and another portion oi a largerdiameter, of an integral, tubular element casing having a reduced, inneropen end and an enlarged, outer closed end, said closed end providedwith means for accommodating and holding a heatable tool, said closedend secured to, but distanced from the end of the housing portion of thelarger diameter, an insulating member disposed within, and next to theenlarged end of said casing, a heating element within said casing,hermetically sealing and terminal supporting closing means at the inneror open end of the casing, terminals extending from said closing means,an insulator extending from said casing into and beyond the housingportion of the smaller diameter and provided with a pair ofthrough-passages for receiving said terminals, these passages ending inchannel formations, the ends of the terminals extending into saidchannel formations and being connected with external electricconductors, their connections being bent back and secured in saidchannel formations, a handle in engagement with the housing portion ofthe smaller diameter and extending over said insulator, and attachingmeans connecting said housing with the handle, arranged within thehandle material and below its outer surface, so as to preclude contacttherewith.

4. An electric heating device comprising an outer housing havingenlarged and reduced portions, a one-piece heating element casing withinthe enlarged housing portion and provided with a closed, enlarged end,forming an integral part of the casing, said enlarged end extendingbeyond said housing portion, the other end of said casing being open, apair of undulated terminals in rictional engagement with the interiorof, and extending from said casing, hermetic sealing means provided atthe open end of the casing and immovably holding said undulatedterminals by way of their undulations.

5. An electric heating device comprising an outer housing havingenlarged and reduced portions, a one-piece heating element casingassociated with, disposed within and spaced from said enlarged housingportion, said casing having at one end a closed head provided with arecessed portion to which the housing is secured, the unrecessed part ofthe head extending beyond the housing and forming one end of the device,the closed head forming an integral part of said casing, the other endof said casing being open, a pair of undulated terminals in frictionalengagement with the interior, and extending from the open end of saidcasing, hermetic sealing means provided at the open casing end andimmovably holding said undulated terminals against disengagement fromsaid casing by way of their end undulations.

6. An electric heating device as per claim 5, a dielectric terminalguide disposed within and extending beyond the reduced housing portionand provided at its outer end with longitudinally arranged means foraccommodating twisted connections between said terminals and exteriorelectric conductors.

'7. An electric device as per claim 5, a dielecn tric terminal guidedisposed partially within and extending beyond the reduced housingportion and provided with through passages terminating in enlarged,longitudinally arranged channel portions for accommodating the twistedconnections between said terminals and exterior electric conductors, anda hollow handle associated with the reduced housing portion and soarranged as to accommodate the extending end of said terminal guide.

8. An electric device as per claim 5, a one-piece substantiallycylindrical dielectric terminal guide extending from said hermeticsealing means of said casing throughout and beyond the reduced housingportion, and provided with a pair of through passages terminating at theouter end of the guide in channel formations for accom- Cil modating thetwisted connections between said terminals and exterior electricconductors, said channel formations constituting longitudinally arrangedcontinuations of said passages, a hollow handle associated with the endof the reduced housing portion and accommodating the channeled end ofsaid guide, and handle attaching means in engagement with the reducedhousing portion, and disposed within the handle material and below theouter surface, for precluding contact therewith.

LEONARD P. YOUNG.

